1. Field of the Invention
The present invention relates to techniques for marking containers for use in wellbore operations. More specifically, the present invention relates to techniques for identification and/or data collection of containers for well site specimens.
2. Background of the Related Art
Wellbores are drilled to locate and produce hydrocarbons. A string of downhole pipes and tools with a drill bit at an end thereof, commonly known in the art as a drill string, is advanced into the ground to form a wellbore penetrating (or targeted to penetrate) a subsurface formation of interest. As the drill string is advanced, a drilling mud is pumped down through the drill string and out the drill bit to cool the drill bit and carry away cuttings and to control downhole pressure. The drilling mud exiting the drill bit flows back up to the surface via the annulus formed between the drill string and the wellbore wall, and is filtered in a surface pit for recirculation through the drill string. The drilling mud is also used to form a mudcake to line the wellbore.
It is often desirable to perform various evaluations of the formations penetrated by the wellbore during drilling operations, such as during periods when actual drilling has temporarily stopped. In some cases, the drill string may be provided with one or more drilling tools to test and/or sample the surrounding formation. In other cases, the drill string may be removed from the wellbore (called a “trip”) and one or more wireline tools may be deployed into the wellbore to evaluate the formation. Such drilling tools and wireline tools, as well as other wellbore tools conveyed, for example, on coiled tubing, are also referred to herein simply as “downhole tools.” During formation evaluation, including sampling and/or testing, performed by such downhole tools may be used, for example, to locate valuable hydrocarbons and manage the production thereof.
Formation evaluation often requires that fluid samples from the formation be drawn into a downhole tool for testing and/or sampling. Various devices, such as probes and/or packers, are extended from the downhole tool to isolate a region of the wellbore wall, and thereby establish fluid communication with the formation surrounding the wellbore. Fluid may then be drawn into the downhole tool using the probe and/or packer. Examples of a wireline formation evaluation tool are described in U.S. Pat. Nos. 4,860,581 and 4,936,139. Coring tools are also used to drill and remove core samples of the formation. Such core samples may be contained in sleeves. Examples of coring tools and associated sleeves are described in US Patent Application No. 2004/0140126. Formation evaluation may also be performed in some drilling tools provided with such capabilities as described, for example, in U.S. Pat. No. 5,803,186.
Samples taken during wellbore operations are usually collected in containers. For example, formation fluid samples drawn into the downhole tool are collect in sample chambers and retrieved to the surface. Similarly, core samples are sometimes contained in sleeves to protect the integrity of the sample as it is retrieved and transported. Other samples, such as mud, frac fluids, etc., may also be collected at the wellsite. The collected samples are often sent to labs for testing. Presently, samples are either removed individually from a downhole tool and placed in bins that are manually labeled, or that are shipped directly to and removed by a test lab.
Throughout many industries, various techniques have been developed for identifying products. Bar code labels on groceries is an example of an identification system that may be used to mark and identify containers and the items therein. Marking systems have been used in downhole applications, for example, for core samples taken from downhole formations. An example of such a system is described in U.S. Pat. No. 5,310,013.
Despite such advances in marking for various products, there remains a need for a system capable of identifying containers and specimens, such as samples, contained therein as they are used at a wellsite and/or transported to other locations. It is desirable that such a system provide a marker associated with a container for collecting various specimens associated with a wellsite. It is further desirable that the system be capable of providing one or more of the following, among others: a marker adapted to receive data associated with a container and/or its contents; a reader capable of reading the marker at an offsite, downhole and/or surface location; a scanner capable of recording data to the marker; and a processor adapted to manipulate the data associated with the marker.